BAKEK'S NEW MICROSCOPES 



2I 9 



top plate is provided with three adjustable stops, so that the centre of 

 a 3 x 1 or 3 x IT? slip is identical with the optic axis when both 

 the rectangular movements are at the centre of their travel, thus 

 enabling any desired field to be recorded: the stage clips are 



FIG. 175 (1852). 



mounted on two of these stops, all of which are removable ; 

 a centring sub-stage of universal size (1*527 in.) with diagonal rack 

 and pinion focussing adjustment, plane and concave mirrors ; the 

 whole mounted on a solid tripod stand, with a bracket to support the 



